Spray booths



Jan. 10, 1956 A. S. MELLOR SPRAY BOOTHS Filed Feb. 2. 1953 InventorAlf/ed S Mellor' y his Attorney United States Patent SPRAY BOOTHS AlfredS. Mellor, Beverly, Mass., assignor to United Shoe MachineryCorporation, Flemington, N. J., a corporation of New Jersey ApplicationFebruary 2, 1953, Serial No. 334,557 2 Claims. (Cl. 98-115) Spray boothsof the type shown in Letters Patent of the United States No. 2,310,205,granted February 9, 1943, on the application of Charles C. Bell forimprovements in cement spraying units, are used in the manu- 'acture ofshoes, for example, where parts of the shoes are to be coated by meansof a spray gun. One of the materials commonly employed is a solution oflatex and since it is impossible to confine the spray exactly to theparts to be coated, there is necessarily a portion which would bedisseminated through the air of the room were it not drawn off by airexhausting means. Such booths as in the patented structure usuallycomprise a work receiving opening at the upper front portion, an exhaustopening at the rear lower portion and may be provided with a fan foreffecting a circulation of air through the exhaust passage between thetwo openings, which passage frequently is constituted by the casingitself. The use of filters, of various sorts, in such casingstransversely of the exhaust passage is well known and various expedientshave been tried to lessen the cost of the filters which, in the case oflatex sprays, are apt to become so saturated that they are no longerserviceable to permit the passage of a current of air. If this happenstoo quickly the cost to the user of the booth becomes excessive. At thesame time it is important that the whole of the unused spray shall beremoved from the current of air so that it may not be disseminatedthrough the room where the booth is located.

An important object of the invention is to provide an improved filter inwhich the cost of maintenance is low. As illustrated, this consists oftwo superposed filters one of which includes a sheet of textile materialsuch as cheesecloth and which may be discarded, and the other of whichis some commercial form of filter such as the Fiberglas filters employedin air conditioning systems.

Another object of the invention is to provide a filter supportingstructure, which will permit the filters to be removed through the workreceiving opening, and when replaced will guide these filters readilyinto place with'a vertical spacing between the two so that any sprayedmaterial which passes through the upper filter will be scattered over alarger portion of the lower filter.

These and other objects of the invention will best be understood from aconsideration of the following specification taken in connection withthe accompanying drawings in which,

Fig. 1 is an angular view of the whole spray booth, with portions brokenaway;

Fig. 2 is a detail horizontal section taken through a corner of thecasing on the line II-II of Fig. 1; and

Fig. 3 is an enlarged vertical section on the line 2,730,033 PatentedJan. 10, 1956 III--IlI of Fig. 1 showing a portion of the means forsupporting the filters at the left side of the casing.

The booth shown in the drawings has a frame made up of angle-iron cornerposts 10, 12 at the front and 11, 13 at the rear. 'Side plates 14, 16have been applied to these posts and attached thereto by screws 18.. Thefront margins of the side plates 14, 16 are bent inwardly to formreinforced hollow corner pockets 20. The front of the casing has awork-receiving opening 22 between an upper front plate 24 having aninturned lower edge 26 and a bottom front plate 28 having an inturnedupper edge portion 30.

The top of the casing is formed by a cover plate 32 and on this there issupported an instrument board 34 for various control devices such as aredescribed in the aforementioned patent. A spray gun 36, carried by anarm 38, is adjustably supported upon a transverse shaft 40 carried bybrackets, such as the one shown in Fig. 2 at 42, which are secured tothe angle iron corner pieces 10 and 12. On this cross shaft 40 there ispivotally mounted an arm 44 arranged to actuate the trigger of the gun.This arm extends beyond the front plate 24 into the corner pocket 20 andis joined there, pivotally, to an upright treadle rod 46 which extendsdownwardly through the corner pocket to a point near the bottom of themachine where it is joined to an arm 48 mounted on a transverse shaft50. The shaft has a treadle 52 normally held in its upper position by aspring 54.

An exhaust opening 56 is provided in the back wall 60 of the casing andit will be noted that the upper portion 62 of this wall is tiltedslightly forward so as better to direct downwardly the current of airpassing through the casing. A fan 64 operated by a motor 66 is effectiveto cause a current of air, passing into the work receiving opening 22,to go downwardly through an exhaust passage formed partly by the hollowcasing and to be driven out through the exhaust opening 56. By locatingthe treadle rod 46 in the pocket formed by the marginal portion 20 thereis little danger of damage to this rod by physical contact therewith andno opportunity for it to become coated with cement so as to requirecleaning.

Near a mid portion of the exhaust passage the casing is provided withmeans for supporting one or two Fiberglas or other mineral wool filters70 which are made up in pasteboard packages for ease in handling. Thesupport of these filters is efiected by narrow strips or ledges 72across the front and rear of the casing, these strips being supported byangle irons 74 attached to the corner posts at front and rear such asthose shown at 10, 11 and at 12, 13. At the ends of the strips 72 andextending from front to rear along the sides of the casing are hollowsheet metal guides 76 having straight guiding surfaces up and down theirvertical faces. These guides are secured by screws 79 to these strips 72and to the angle irons 74.

The upper faces 78 of the hollow guides 76 are inclined downwardly andinwardly to facilitate the dropping into position of the Fiberglasfilters 70. They are also provided with notches forming shoulders 80 onwhich are rested the margins of a hollow frame 82. This is a rectangularstructure of angle iron strips having inturned bottom edges 84 and it isprovided with upstanding pointed screws 86 along all four margins toreceive and position a sheet of cheesecloth 88 in stretched or fiatconditions. It will be noted that the frame fits within the uprightportions 90 of the notches in the guide members but for convenience itshould not be brought too closely to said upright portions. Accordingly,it is found preferable to cut the sheet of cheesecloth 88 to such a sizethat. it will extend across the gap between the frame 82 and the uprightportions 90 to prevent any accumulation of cement therein which mightinterfere with the is relatively inexpensive, it can be changed as oftenas is required without incurring any considerabletexpense. It

' is found, however, that several hundred shoes willhave been workedupon before such change isnecessary, while the Fiberglas filters, withsuch an arrangement, need replacement only once or twice a year. It willbe noted furthermore that the operator is able to tilt theframe 82slightly to facilitate'its removal through the work receiving opening30, and that the positioning of this frameor of the Fiberglas filters incorrect relation to theexhaust passage is greatly facilitatedby theguide members 76 and the shou1ders'80 therein. At the same time the inelined upper faces 78 of saidmembers help to guide the filter memberswhen they are put back throughthe opening and dropped into place.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

1. In a spraybooth having a work receiving opening and an exhaustpassage, means beneath said opening for supporting a mineral woolfiltertransversely of said .p'assage, guide members superposed on vsaid'meansto allow said filter to drop into place and to position said filterlaterally, a cheesecloth-carrying hollow frame, said guide membershavinginclined top portions extending to the adjacent side walls to facilitatethe positioning of the filters and having means supporting the hollowframe at a postion above said filter, and means for holding a piece ofcheesecloth ontsaid frame with itsmargins resting on the inclined topportions of the guide members.

2. In a spray booth, a'substantially rectangular upright casing having,at its upper front portion, a work receiving opening, the casing alsohaving an exhaust opening at a lower level and constituting a verticalexhaust passage, ledges on said casing along two sides thereof forreceiving and supporting a mineral wool filter, upright guide membersadjacent to said ledges having side walls and inclined top surfaces,said guide members extending transversely of the casing along theremaining sides, means fastened on the casing supporting the ledges andthe guide members, the bottom portions of the side walls of the guidemembers serving to transversely locate the position of the filter, ahollow frame larger than said filter for another filter, the inclinedtops of said guide members being notched to provide upright sides andshoulders to receive said hollow frame at a levelspaced above the firstfilter, the upright sides of said notches being spaced in the passage totransversely locate the position of the hollow frame on said guidemembers, saidframe being provided with sheetpositioning and holdingmeans, andra sheet of textile material positioned on thehollow frame andhaving marginal portions overlying and extending beyond the sides of theframe which rest upon said notches to touch the casing, thereby toprevent the accumulation of sprayed material on said guides which wouldinterfere with the removal of the hollow frame.

References Cited in the file of this patent UNITED STATES PATENTS1,134,294 'Supanz Apr. 6, 1915 1,431,909 Garrett Oct. 10,1922 1,854,569Wclch Apr. 19, 1932 1,896,700 Cross Feb. 7, 1933 2,106,187 Naugler Ian.25, 1938 2,310,205 Bell Feb. 9, 1943

